SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '264671a4f51ac0910c505c5909cadfcfb46316ad63c3adf8194ffe863b0555b1' 
  AND token = 'R2ijPvm6WlaYefCsV1BWa8llEBW3y+x6iuXPMzrk8tU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}